Many other comments here have a share in the reasons, but a huge reason is he’s looking at more state and federal charges, and more lawsuits (which haven’t going well for him).

He NEEDS to run and WIN so he can make all these cases go away for good.

1. metacognitive myopia explained why people didn't/couldn't update their beliefs about the existence of "weapons of mass destruction etc".
2. dogwhistling the threat of sexual revolution "comrade kamala" (i.e., he's implying hypocrisy when he doesn't understand what lenin's use of the term "prostitute" meant).
3. playing the fool until you can't (i.e., making his base feel insightful and "seen" as playfully serious, homophilically/mimetically charismatic; e.g., his base feels like their inference-making is being promoted based on linguistic sympathy through the aura of charisma).
4. from (3) somewhere in his administration they're letting the would-be "fool" base do the grunt-work and creating cover; see "Optimal Team Formation Under Asymmetric Information".

Seriously, how the f*** is this guy still in the race?

It's depressing as hell that this is where we are.

ignorance-based fear.

lot of that in a geographically isolated country with poor education.

A technical reason is because he has been a president before

I think a lot of Americans like to feel special/different/superior and Trump helps feed that addiction

You have to remember that the voters are human beings, complete with areas of ignorance, prejudices, and logical fallibility. Trump certainly is aware of that and exploits it to the maximum extent.

I'm not from the US and so it's officially not my business. But from what I've seen around the webs is that he has gathered a loyal following all around the US. Seems he has enough loyals on his side to stay in the race. But I don't know a lot about the political system in the US. Excuse me if I'm wrong here.

Money and bigotry

Some voters arestill "undecided" because "both sides are the same" (aka they don't know how to tell fact from fiction)

Rich donors who don’t want EU like welfare states in the U.S.

He is a cult leader. More than a decade in the making. Hes the leader of a cult

not making her talking points about her race or gender like Hillary

The difference between someone who lived the struggle and someone who was just trying to represent it.

Racism and cult mentality.

Bigotry, misogyny, and Palestine. If she came out for limiting arms sales to Israel she’d be crushing trump.

Greed and jail is keeping him in the race. Followed by narcissism and the drive for power. (The last 2 are a requirements for a politician of any stripe).

Inertia?

The Overton window has shifted dramatically in the last 10 years. He represents aversion to that

I believe the answer is "A lot of Americans".

Donald Trump, the Man who called our Soldiers Losers and Suckers while Praising our Enemies and Residing over one of the Deadliest periods for our Secret Agents abroad, is a PATRIOT WHO LOVES AMERICA and KAMALA, who is LITERALLY the Vice President right and never Stole any Top Secret US Documents, HATES THIS COUNTRY!

BILLIONAIRE Donald Trump LOVES the Working Class while Prosecutor who went Lenient on First Time Offenders and Non Violent Offenders Kamala Harris HATES the Working Class!

Donald Trump, who Presided over the DEADLIEST YEAR IN AMERICAN HISTORY, will Protect us while LITERAL LAW ENFORCEMENT OFFICER Kamalamala Harris WONT!

Why did the cubs have such a hardcore fanbase despite their legendary drought? A lot of people root for their team, not vote for their best interests.

Just a small correction, there was no coup attempt in Venezuela that's just dictatorship propaganda from Maduro